Induction-motor.



A. M. DUDLEY.

INDUCTION MOTOR.

APPLICATION men ocr. 3. 191a.

1,232,01 2. Patented July 3, 1917.

. WITNESSES:

ATTORNEY UNITED sTA'rEs P ENT OFFICE.

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Patented Jul 3, 1917.

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To all whom it may concern; P I w Be it known that I, Anoilr itis M. Drin- LEY, a citizen of the United States and a resident of Pittsburgh, ,in the cou'nty of Allegheny and State otliennsylvania, hare invented a new and useful Improyemept 1n Induction-Motors, of which the following is a specification. v A

My invention relates to induct on motors of the squirrelcage type and it has for ts object to provide a simplean d con venient means for connecting the conductor bars of the rotor to the short-circuitingrings, whereby the rotor parts may be assembled more easily and qulckly. V H

Heretofore, it hasbeen the usual practice to connect the conductor bars of squirrelcage windings to the end rings .b, rivet ng, welding, or similar methods. nle these constructions insure stability and good elec trical contact, if the operations haye been properly performed, they ,involve, the expenditure of a large amount, or time and labor which constitutes a material item in the cost of manufacture. 1

In carrying out my invention, I employ conductor bars that are provided with screw threads for engagement with correspond ingly threaded openings in the Sh0It -C1I- cuiting end rings. The bars are provided with heads adapted to be engaged by suitable tools for turning the bars into place.

By means of this connection, the bars can be securely attached to the end rings by the simple operation of turning the same with a wrench or other tool. Good electrical contact between the several bars and the rings is insured because of the production of clean engaging surfaces by means of the sliding engagement of the threads under pressure.

In the accompanying drawings, Figure 1 is a longitudinal section of a portion of the rotor of an induction motor embodying my invention. Fig. 2 is an enlarged view of a conductor bar. Fig. 3 is an end view of a portion of the rotor of an induction motor showing a conductor bar in position parts being broken away. Fig. 4 is a detail v ew of a modification of the conductor bar of Fi 2.

fteferring particularly to Fig. 1, in which is illustrated only half of the rotor 1 of an induction motor, a laminated core structure 2 is supported by a spider 3 and end plates 4.. The core 2 is provided wita artiany inclosle'd slots 5 as best sho s iii Fig. '3, .to receive conductor bars 6 of the squirrelc age winding. End,rings 7 and 8, which short-circuit are conductor bars 6, are each provided with alternately disposed threaded openings 9 and 10, respectively, that register with correspondin slots 5. (The openings 9 have a greater 'iarneter than the openings 10. I

'Qhe conductor bars 6, one of which, is shown in; detail in F 2, are each provided at one end with a square head 11 for engagement with a suitable wrench or other turning means, and a screw threaded portion .12 for engagement with athreaded opening 9. The. body portion 13 of the conductor 6, which is substantially cylindrical in shape, is smaller in diameter than the threaded portion 12 in order, that it may be readily, inserted thro lgh the correspondingly, threadedopenin g 9 in the end rings Me 1 .J e.sq ander ewa also i vided at the opposite ends with a threaded portion ,let forengagement withthe correspondingly threaded openings 10 in the end rings.

In assembling the rotor windin alternate conductor bars 6 are inserted rom opposite ends of the rotor through the openings 9 and the slots 5, until the threaded portions 12 and 14 are in a position to engage the threads of the respective corresponding openings 9 and 10. The bars are then turned by means of any suitable tool which engages the square heads 11 until they are advanced into their proper positions. By applying approximately the same torque to each of the conductor bars, a uniform tension may be placed upon them and the electrical resistance of the several connections will be substantially the same. If the pitch of the screw threads employed to connect the threaded portions 14 with the threaded openings 10 be made slightly greater than that of the threaded portion 12 and the openings 9, the bars 6 will draw the end rings 7 and 8 toward each other to tightly clamp the core structure as the bars are turned into position.

Fig. t illustrates a modification of the conductor bars 6. At the headed ends of the bars, the threaded portions 19. are replaced by cone-shaped portion 15 to engage corresponding openings (not shown) in the end rings 7 and 8. By means of this arrangement, the end rings can be drawn tightly together and the same time a rigid construction and good electrical contact may be secured.

I claim as my invention:

1. In -a mptor winding, the combination with a conductor having threaded portions of difierent diameters, and conductors having correspondingly threaded openings to be engaged by said threaded portions.

2. In a motor winding, the combination with a plurality of conductors having threaded portions of different diameters, of end rings for shortcircuiting said conductors, said rings having threaded openings to reeeive'said threaded portions.

3. In a motor winding, the combination with a plurality of conductor bars each having an angular portion and threaded portions at the ends of the same, the threaded portions at one end of said bars being larger than the other portions, of end rings having threaded openings for engagement by the threaded portions of said bars.

4. In a motor winding, the combination with plurality of conductor bars having threaded portions of different diameters, of end rings for short-circuiting said conductor bars, said rings having threaded openings of different diameters, alternately spaced to receive said threaded portions.

5. In a motor winding, the combination with a magnetizable core member having slots and conductin end members provided :-'5

with a plurality o threaded openings, of conducting bars located in said slots and havin threaded portions coacting with the threa ed openings in each of said end members to draw said end members together.

6. In a motor winding, the combination with a magnetizable core member having slots and conducting end members provided with a plurality of threaded openings adapted to register with the said slots, of aplurality of conductor bars adapted to be inserted into certain of said threaded openings and said slots, and having threaded portions coacting with the threaded openin s in each of said members.

I. In a dynamo-electric machine, the combination with a magnetizable core member having slots and conducting end men'ibers provided with threaded openings of different pitch adapted to register with said slots, 1

of conducting bars located in slots and hav' ing threaded portions of different pitch coacting with said threaded openings to draw said end members together.

In testimony whereof, I have hereunto subscribed my name this 26th day of Sept.

' ADOLPHUS M. DUDLEY. Witnesses:

O. C. Sononnrnm, B. B. HINES.

Copies. this patent may be obtained for five cents each, by addressing the Commissioner 0! Patents, Washington, D. G. 

